The present invention relates to a housing, in particular for the installation of electrical and electronic components, consisting of a housing lower section and a cover, fixable thereto, for the installation of electrical and electronic components.
Commercially available housings, primarily made from aluminium but sometimes also from glass-fibre reinforced polyester or thermoplastic materials are provided in the lower section of the housing in the regions of the corners with a tapped hole for affixing a cover which is provided, for this purpose, with through bores with a lowering for the screw head. For reasons of saving material and weight a canal is provided adjacent to the tapped holes axially aligned with said holes and extending through to the bottom side of the lower section, the clear widths of said canal being larger than the cross-section of the tapped hole. One mounting canal each extends in parallel to the aforesaid canals and usually immediately adjacent to them, extending from the top side of the lower section through to the bottom side of the lower section. This canal serves for mounting the lower section to a support. At its lower end it is stepped down to a smaller clear width, thus creating a circular bearing surface for a screw head.
Users of such housings often have the desire to connect the housing lower section and the cover in such a manner that a cover hinge ensues. Often, electrotechnical and/or electronic components are mounted in the housing lower section and in the cover, such components being connected to each other by cables or wire buses. It is important to avoid that such connections are subjected to tearing when the cover is open. Hereby, for various reasons, users of housings prefer internally disposed cover hinges, i. e. hinges which are not visible on the outside when the cover is closed.
These demands are met by a metal wire hinge disclosed in DE 92 16 735 U1. Said hinge consists of a piece of metal wire one end of which is rolled into a cover screw. Said cover screw, for this purpose, is provided with an axial pocket bore into which the piece of wire is inserted prior to rolling-in. A thread plug is rolled-in to the other end of the metal wire in a similar manner, the cross-section of the thread of said plug co-inciding with that of the cover screw. Thus, the cover screw and the thread plug are connected with the piece of metal wire in a torsionally fixed manner. In order to assemble the hinge, the end comprising the thread plug is slid through the cover bore and then screwed through the thread bore in the housing lower section provided for the cover screw. As the thread bore, as explained above, widens into a canal towards the bottom, the metal wire hinge in total drops into the canal up to a point where the cover screw comes to rest with its lower end on the housing lower section. Now, the metal wire hinge can be drawn back only up to the point where the upper end of the thread plug comes to rest against the lower end of the thread bore. The cover screw can now be screwed into the thread bore of the housing lower section. This mounting procedure is repeated at the other end of the same side of the housing. Now, the other cover screws may be screwed in.
To open the cover all cover screws, including those integrated into the metal wire hinge, are unscrewed from the thread bores of the housing lower section. The cover can then be pivoted about its hinge side. Hereby the metal wires are pulled out of the canals up to the point where the top sides of the thread plugs come into contact from below with the thread bores. Thus, the thread plugs in conjunction with the lower side of the thread bores act as stoppers. Hereby, the length of the pieces of metal wire is dimensioned such that the desired angle of pivoting for the cover is attained. The cover is held at its outer side by the cover screws of the metal wire hinge which rest in the cover bores.
In practice it has become apparent that such known metal wire hinges are subject to disturbance as the roll-ins of the ends of the metal wires are not always securely fixed. Moreover, such hinges are relatively costly to manufacture.
A further disadvantage is that the above described metal wire hinge must be held available by housing manufacturers with differing screw heads (slotted head, interior hexagonal head, as desired by the customer). Expenditure for warehousing is still increased by the fact that various lengths of cover screws are required for different cover thicknesses.
A housing described in DE-OS 20 29 983 bears the same or similar disadvantages. Hereby, the connecting member of cover and housing lower section consists of a knurled actuator button to which one end of a flexible shaft, preferably made from thermoplastic material, is affixed. Said shaft runs in the mounted state through an elongated tube which is rotatable and axially displaceable in relation to the shaft. At the other end of the shaft a cap is affixed by a screw connection.
In order to affix the cover to the housing lower section, initially the shaft of the connecting member with the actuator button affixed thereto is inserted from above through a through bore in a corner of the cover. Subsequently, the tube is slid onto the shaft from below and the cap is screwed onto the end of the shaft facing away from the actuator button. Now, the tube can no longer slide off from the shaft as the cross-section of the cap is larger than the smallest interior cross-section of the tube in its upper area. The lower area of the tube which is provided with a thread on its outside is now screwed into a thread bore of the housing lower section. To this end, a central section of the tube is provided in hexagonal shape such that an open end wrench can be used. Now, the cover is placed on top. The tube is so long that its upper end provided with the outside thread extends into the through bore of the cover. The actuator button is provided with a downward protrusion in the shape of a hollow cylinder with an interior thread. By means of said thread the actuator button is screwed onto the upper end of the tube, thus firmly affixing the cover to the housing lower section. The connection described is realized in identical form in the other corner of the same side of the housing.
In order to detach the connection, the actuator buttons are unscrewed from tubes. As the shafts are of sufficient length, the cover can be lifted off the housing lower section and tilted up to the point where the caps come to rest against the smaller interior cross-sections of the tubes. The cover is now suspended from the housing lower section and cannot become lost.
A further interior hinge to be disposed in the screwing canal of a housing is described in DE 196 00 260 C1. Said interior hinge comprises each a tubular upper member and a lower member whereby said two members are connected with each other in the form of a hinge. The lower member is provided with a interior and an exterior thread. The exterior thread is screwed into the housing lower section. In order to affix the cover to the housing lower section, a screw is inserted through the tubular interior hinge and screwed into the interior thread of the lower part of the interior hinge at its lower end. The upper interior hinge member is also provided with an interior thread of the same cross-section as the interior thread of the lower interior hinge member. In order to detach the cover, the screw is unscrewed from the interior thread of the lower interior hinge member. Upon lifting the cover from the housing lower section the screw in the upper interior hinge member is displaced up to the point where the thread member comes to rest against the interior thread of the upper interior hinge member.
Then, based upon the flexible connection between the upper and the lower interior hinge member, the cover is suspended from the housing lower section.
DE 199 24 168 A1 describes a fixation device for connecting two housing halves of an installation device. In this fixation device an first housing half is provided with at least one bolt rod the end of which is provided with at least one snap hook. The second housing half is provided with a connector platform with a recess suitable for inserting the snap hook. The recess is provided with an undercut for arresting the snap hook.
It is the object of the present invention to define a housing in accordance with the type described above which overcomes the described disadvantages.
This task is solved in accordance with the invention by a housing comprising a housing lower section and a cover connected to each other in a hinged manner by at least two flexible inner elements that are separated from each other outside the sealed inner chamber of the housing, wherein the ends of the flexible inner elements have a greater cross-section than the region between the ends, whereby at least one of the ends is elastically embodied by a temporary reduction in cross-section and, through openings leading into each other, are positioned in the cover and the housing lower section, the cross-section of which permits access of the at least one end in the compressed state, which end, after access through the corresponding through opening, increases in cross-section again through elastic relaxation.
The housing in accordance with the invention allows for very simple and quick assembly of its flexible interior elements which serve, when the cover is open, as tension relief for cable connections between components mounted in the housing lower section and in the cover. If both ends of these elements are provided with a compressible thickening these must be slid from below or above respectively through the through openings in the cover or the housing lower section respectively until the compressible thickenings, having passed the through openings, re-expand and lock behind the edges of the openings. Following this assembly procedure the cover is affixed to the housing lower section in the manner of a hinge.
It goes without saying that the lockings are dimensioned in strength such that they do not yield under the load of the cover and components possibly mounted therein hanging from the flexible interior elements, i. e. guarantee safe hold of the opened cover on the housing lower section. Hereby, the opening angle of the cover is determined by the length of the flexible elements, as known in the state of the art. If only one end of the flexible elements is provided in compressible form and the other in more or less rigid form, the assembly must be carried out such that the flexible element with its compressible end is slid successively through the through openings of the cover and the housing lower section, or vice versa, until it snaps back and locks behind the edge of the opening of the cover or the housing lower section respectively.
In an advantageous embodiment of the invention the flexible interior elements are designed as injection moulded plastics member with an integrated compressible lock element at one end and an integrated thickening at the other end. Such an injection moulded member is very inexpensive to produce so it can be packed with each housing as an option for the user of the housing without extra charge. With all prior known solutions users of housings must pay an additional price for the flexible hinge elements as they are relatively expensive to manufacture.
Furthermore, it is advantageous to design the through openings in the cover to receive the integrated thickening in a form-fit and flush manner. Thus, this end of the flexible elements does not protrude from the surface of the area of the cover surrounding the through opening. At the same time, it closes the cross-section of the through opening so that an optically pleasing appearance ensues.
Advantageous further aspects of the invention will become apparent from the following detailed description.